1. Field of Invention
This invention is generally related to microwave cooking devices and is specifically directed to a microwave cooker that cooks food at a constant pressure while minimizing oven clean up.
2. Description of Prior Art
Conventional cooking methods are often duplicated in a microwave oven. Just as in stove top cooking, steaming and boiling food in the microwave requires careful monitoring in order to avoid spattering or spilling food. Loss of food during preparation effects the outcome of the recipe and makes clean up burdensome. Moreover, regulating pressure build up inside a microwave cooker during the boiling or steaming process is critical to avoid an explosion.
A wide assortment of cookers boil and steam heat food inside the microwave oven. Some have a complex structure, others are simple. Yet, no cooker continuously alleviates pressure build up inside the food chamber while at the same time minimizing the mess created by boiling foods.
For example, U.S. Pat. No. 4,705,927 presents a microwave cooker designed specifically to steam heat food. This device features a separate water absorbing member to generate steam. The member controls heat distribution and reduces cooking time. However, pressure build up is not continuously released from the food container, or does the cooker obstruct food from splattering or pouring over into the oven.
The device of U.S. Pat. No. 4,839,484 boils rice in a microwave oven. The cooker employs an open bowl inverted and positioned at the bottom of another bowl. The inverted bowl contains slits that circulate water. During the cooking process, the water must be periodically discharged and new water added. A lid supporter prevents overflow and scattering of boiling water within the food container. However, pressure is not adjusted, nor pressure build up alleviated, without shutting off the oven. Also, this cooker does not have a lid enclosure which prevents food from overflowing into the oven.
Similarly, U.S. Pat. No. 4,271,344 is directed to cooking and softening foods, without dehydration or loss of moisture content. A heating chamber contains a plate having a plurality of apertures in a predetermined pattern for the passage of vapor. The plate is designed to obstruct food from projecting above a liquid level. The cooker further contains a shield lid made of metallic material causing a portion of the high frequency electromagnetic waves to be reflected before reaching the food. However, nothing is offered to equalize pressure.
Microwave cookers of simple construction, without special designed implements or separate compartments, also lack the necessary mechanisms that relieve pressure build up and prevent food spattering and spillage. For example, U.S. Pat. No. 4,478,349 is an uncomplicated device to heat and cook both food and beverages in a microwave oven. This microwave cooker features an insulated dish having a double walled vessel construction and lid. An air cavity separates a removable inner container from an outer container of similar shape. A flange and rim assembly support the inner container and allow pressure to escape from the air cavity. However, nothing relieves pressure build up within the inner chamber containing the food. Moreover, no implement ensures that the lid stays closed and the food stays inside the dish.
Likewise, U.S. Pat. No. 4,952,765 offers a microwave cooker comprising a container for holding food, an outside lid and an inside cover. This cooker features an inside lid which shuts off vent holes during the microwave heating, deliberately halting any dispensation or flow of vapor from the container. Although simple to manufacture and use, the cooker does not release pressure build up until the microwave oven is turned off.
Hence, a need exists for a microwave cooker of simple construction that relieves pressure build up during continuous microwave processing while impeding the spattering of food throughout the microwave oven.